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<a href="index.html">Journal</a>(2005) | <a href="../blog/"><b>Blog</b></a>(2006) | <a href="http://www.fayland.org/cgi-bin/random_link.pl">RandomLink</a> | <a href="AboutFayland.html">WhoAmI</a> | <a href="LiveBookmark.html">LiveBookmark</a> | <a href="http://www.fayland.org/">HomePage</a>
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<h1>DBI</h1>
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<p>Category: <a href='Basic.html'>Basic</a> &nbsp; Keywords: <b>DBI</b></p><ol>
<li>判断顺序<br />
<pre>
if (!defined ($a)) { print "NULL"; }
elsif ($a eq "")   { print "empty string"; }
elsif ($a == 0)    { print "zero"; }
else               { print "other"; }
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<strong>Related items</strong>
<ul><li><a href='050330.html'>Class::DBI 改 Primary 项</a> < <span class='digit'>2005-03-30 22:27:07</span> ></li></ul>
Created on <span class="digit">2004-10-30 18:50:50</span><br />
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